Means for heating windows or transparent panes for aircraft, motor cars, or the like



ATTORNEY.

INVENTOIC V/odm/ W ALL Patented Jan. is, 1942 ITE-1)v 1 STAT ESSv PAT-EN T 'O FF I CE 2,269,566 Masas Fon HEATING wmnows on'rasns- `PermianPalmas Fon smelten. Moron oAasoarnamxa y f Gen-1t van naam, prima, N. Y. application rune 1o, lesa-semi No. 278,446 (c1. 21a-19) vMy invention relates to improvement 'in means 3 Claims.

for heating windows or transparent panes for aircraft,l motor cars, or the like. The object is to provide neans for heating said window or panes so 'that the same will not become clouded or frosted during inclement @atmospheric conditions.

My invention comprises means-whereby stand- Fig. 'l is a diagram of a rh/eo'stat control.

Similar numerals refer to similar parts throughout'the several views. v In accordance with the example illustrated in the drawings a rectangular spacing frame is provided consisting of the members i5, I6, i1

and i8, preferably of non-conducting'material.

VThese members are connected together -in any suitable way. Thesheets or panes I9 and 2li of transparent material have outside dimensions s corresponding with the outsilde dimensions of the for suspending, under spring or elastic tension,

an electric resistance strand, ribbon or -wire,

evenly between two sheets of transparent matetained midway between said sheets and in prop- .erly spaced relationship.`

tween said brackets and strand. This arrangement-is useful, not only for suspending and maintaining the strand in proper position under varying temperature and atmospheric conditions, but' also to provide a substantial Space between the strand and the supporting frame members,.in

separating frame.4 These sheets or panes are placed, one on each side of the frame and are Y packing, such as indicated at 22. v rial, whereby the strand extensions are mainf The upper and lower horizontal elements I1 and I8 are provided with slots 23 in which the 4ends of U-shaped formations or brackets 24 are order that the heat deliveredl by the resistance 'Referring to the drawing which illustrates merely by way of example suitable means 'for efiecting the invention:

Fig. i is a view in elevation. Fig. 2 is a fragmentary elevation showing a modication.

F18. 3 is a'section on the line 3--3 of Fig. 1. Fis. 4 is a section on the line 4 4 o f Fig. 1.

secured. These slots 23 are provided rwith shoulders or projections 25 to maintain the bracket ends or trunnions 24 in proper position. The parts of the separating frame members between thev vertical arms of projections 25, are tapered lasshown at 25' to provide iiaring air spaces between said -vertical arms and the adjacent parts of theframe. These brackets 24 are in loop, or U-formation and areadapted to receive the ends of springen, to the other ends of which is secured each extension o'f the resistance strand 21.

In Fig. 5 a' modiiication'is shown in which `yokes 2Q are provided, secured to the lower end di' each spring 26, while the resistance 21 is secured, in proper spaced relationship, to thevouter ends 'of said yokes.

The upper` and lo'wer horizontal members I1 and I8 are substantially the same in construction, and the strand 21 is threaded forward and backward inl the usual way, except that the sup',-

porting connections with the strand are through springs, or spring 'controlled yokes, so that a con- A Fig.' 5 is adetail in elevation showing the strand suspending means. $18.6 is a similar view of a modification.

tion, and permit the necessary expansion or contraction, due to thermal or other causes. and thus prevent the strand extensions from touching each other and thereby cause a short circuit, and

also to prevent said extensions from touching the surface of the panes.

Where it is desired to use standard plate glass as the transparent panes, I provide a special protection for the same. This protection consists oa sheet or layer i9' (see Figs. 2 and 3), of nonfrangible, transparent material, such, for example, as is known to the trade as Plexiglass, or a thermo-plastic material made of acrylic resins.

This material is practically non-frangible and a poor heat conductor. When applied to the outer face 'of the glass,'it protects the same from sudden and sharp temperature changes which are liable to crack or fracture the glass during the ight in sub-cold temperatures.

The usual circuit connections are provided, such as binding postsfiii and 3i with the wire leads 32 and 33. In Fig. i is shown diagrammatically a suitable rheostat control for the circuit, so that the `heating current may oe applied gradually, and may be'increased or reduced as required by Varying temperature conditions ci the atmosphere; In tins figure, the resistance Sil is provided with stepped contacts Slifer cooperation with the controlling sti/itch in Fig. l is shown a 'port cicsed hy a stopper 33, which may he used icl' introducing, into the space between the panes, when desirable, a

What I claim ist l. in a device of the character described, the combination of a spacing frame, two transparent panes having margins co-extensive with the outer margins of said frame, means securing said panes hermeticaily to the opposite faces of said frame thereby forming a chamber between said panes and within said frame, and a resistance strand having zigzagl extensions within the area bounded by said frame, said chamber containing a liquid for supporting the panes against excessive external pressure.

2. In a device oi the character described, the combination or" a spacing frame, two transparent panes having margins co-extensive with the outer margins of said frame, means securing said panes hermetically to the opposite faces of said frame thereby forming a chamber between said panes and within said frame, and aresistance strand having zigzag extensions within the area bounded by said frame, said chamber containing a non-conducting, non-expanding and non-iniiammabie liquid for supporting the panes against excessive externai pressure.

3. in a device oi the character described, the.

combination ci spacing frame, two transparent panes having margins izo-extensive with the outer ci said frame. means securing said panes hermetically to the opposite faces of said iframe thereby forming a chamber between said panes and within said frame, and a resistance strand suspended within the area bounded by said frame, said chan-.ther containing minerai oil.

GERRY? VAN DAAM. 

